.app{
    width: 400px;
    border: 1px solid red;
    margin: 100px auto;
}
.btnSend{
    float: right;
    width: 80px;
    height:50;
}

.modal{
    position: absolute;
    left:0 ;
    top: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
}
.inputname{
    position: absolute;
    left:40%;
    top:40%;
    color: #fff;
}